Can you plz help me?

Atriangle has sides with lengths of 10 yards, 13 yards, and 18 yards. is it a right triangle?

If the graphs of the linear equations in a system are parallel, what does that mean about the possible solution(s) of the system? a. there are infinitely many solutions. b. there is no solution. c. there is exactly one solution. d. the lines in a system cannot be parallel.

Can someone me and do the problem plz so i can understand it more better